In the last few weeks I have begun to use the Cognisys Stackshot system. The Nikon D850 camera is mounted on the Stackshot rail and a motor turns a screw on the rail advancing the camera a fraction of a millimeter. The control system trips the cameras shutter at each stop allowing a series of exposures to be made at precise focus points. Zerene Stacker is used to compile all the exposures into a single image selecting areas of best focus from each image. I have been getting best results from compiling 100 exposures to create a single image. The camera and Stackshot are mounted on a modified Durst 138 5x7 enlarger. This creates a high resolution microscope optical system with the capacity to capture the micro images of "Stone Spirits".
The Allan Walls Cage Project has additional information on the technology of this setup.